Handheld flashlights with beam focusing feature have been known for years. The majority of such flashlights adopt a complex optical structure to provide its internal light source an adjusting mechanism within a confined space. The more complex the optical structure is, the more likely the components or parts associated with the adjusting mechanism would wear out under rough usage.
The invention seeks to eliminate or at least to mitigate such a shortcoming by providing a new or otherwise improved flashlight unit.